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The LPA team coordinates and reviews engineering plans for the service categories described below. For sewer extensions and direct connections, our staff provides written approval of final plans.

The following is a general process flow diagram of the LPA Program’s five-step review process. Note that the review process and requirements will vary by project based on project scope, schedule, and design; easements and property rights; and LPA staff availability.

General process flow of the LPA program’s review process.

LPA services

The LPA team can help with any requests for information about WTD’s sewer system. Or, we can guide you to other King County resources that will better address your needs.  

The most common questions we receive include the following:

  • Can we get sewer service here at…?
  • Can you provide us record drawings for your facilities at…?

Contact us.

Graphic shows examples of sewer extensions that are connections for new single-family houses, apartments, businesses, shopping centers, restaurants, or schools Sewer extensions are new public sewers connecting to existing local sewers owned by the local agency that connect to the King County sewer system downstream. They are essentially extensions to the local agency sewer. Examples of sewer extensions include, but are not limited to, local public sewers for new single-family houses, apartments, businesses, shopping centers, restaurants, or schools.

Proposals for new sewer extensions need to be submitted to the local agency first to go through their approval process. The local agency then submits the final plans to the LPA team for its review and approval. Approval by the LPA team is in the form of an approval letter sent to the local agency.

Contact us.

Direct connections are sewer connections directly to the KC sewer systemDirect connections are sewer connections directly to the King County sewer system. The connection point can be on a King County pipe, maintenance hole, or sewer stub designated for connections. Please coordinate with the LPA team to locate the optimal point of connection to the King County sewer.

There are two types of direct connections: joint-use direct connections and local agency direct connections.

A joint-use direct connection is a private sewer connection directly to the King County sewer. Examples of joint-use direct connections include, but are not limited to, single-family houses, businesses, gas stations, or restaurants. Requirements for this type of connection are as follows:

  • Proposals for a joint-use sewer connection need to be submitted to the local agency to check for any available local sewer connections.
  • If there is no local sewer service available, please contact the LPA team to coordinate a point of connection to King County’s sewer line.
  • The local agency needs to submit both preliminary and final plans for joint-use connections to the LPA team for review and approval. Approval is in the form of a letter to the local agency.

A local agency direct connection is a new local agency connection directly to a King County sewer pipe, maintenance hole, or stub off the main pipeline. This type of connection allows for future sewer extensions for new housing developments, shopping centers, or businesses. Requirements for this type of connection are as follows:

  • Please contact the LPA team to coordinate a point of connection to the King County sewer.
  • The local agency needs to submit both preliminary and final plans for direct connections to the LPA team for review and approval.

graphic displaying modifications to the King County or local sewer system as a result of other agency construction projects System modifications are alterations or upgrades to the sewer infrastructure, whether they are modifications to the local agency sewer system or to the King County sewer system as a result of other agency construction projects. Examples of system modifications include, but are not limited to, pipe relocations, installing a new pump station, or rerouting wastewater flows. System modifications can be submitted by non-sewer agencies, such as transportation agencies, and can be a subproject as part of a larger construction project that requires relocation of King County’s sewer pipes.

The LPA team makes sure that sewer modifications and any associated construction have minimal impact on the King County sewer system. We coordinate with the local agency, consultant, contractor, and internal King County stakeholders about the project’s scope, design plans, property rights, and easements. Depending on the nature of the project, an interagency agreement is often required between King County and the local public agency.

Please contact the LPA team to verify whether a construction project may impact the King County sewer system. The LPA team is involved from the project’s preliminary design through construction for design review, coordination, King County project requirements, inspection of construction, and acceptance of final modifications.

Construction impacts are projects that involve construction adjacent to, on top, or below KC sewer lines or facilitiesConstruction impacts are projects that involve construction adjacent to, on top of, or below King County sewer lines or facilities. Local agency projects involve potential impacts that may cause damage to the King County sewer system or facilities adjacent to an agency’s project site, if not protected. Examples of construction impacts include, but are not limited to, shoring, pavement overlay, tunneling, and other utility work that requires protection in place of King County’s sewer system.

The LPA team makes sure that any adjacent construction impacts are minimized to protect King County’s sewer infrastructure. The LPA team is involved from the project’s preliminary design through construction for design review, coordination, King County project requirements, and inspection of construction.

Depending on the nature of the project, an interagency agreement may be required between King County and the local public agency.

Please contact the LPA team to verify whether a construction project may impact King County’s sewer system.

Any projects that may directly or indirectly impact WTD’s sewer system, facilities, or infrastructure that don’t fall under any of the above categories.

Contact us.